Targeting Signaling Transduction Pathways in Bladder Cancer

Serum Tumor Markers for Muscle-Invasive Bladder Cancer in Clinical Practice: A Narrative Review

In recent decades, serum tumor markers (STMs) have emerged as valuable adjuncts in early cancer detection and post-treatment surveillance. STMs are inexpensive, minimally invasive, and readily accessible tools that can be used to diagnose cancers, monitor patients' responses to treatment, and even detect recurrence without imposing additional burdens on patients. Emerging evidence has demonstrated the reliability of STMs in the prognostication of bladder cancer (BC). However, their potential role extends beyond prognostication. This review intends to provide a multidimensional picture of STM applications in muscle-invasive bladder cancer (MIBC). In addition, we supplement this review with real-life clinical experiences from our institution to further illustrate the clinical feasibility of STMs in MIBC.

PABPN1 regulates mRNA alternative polyadenylation to inhibit bladder cancer progression

BACKGROUND

About 10-20% of patients with bladder cancer (BC) progress to muscle-invasive diseases, of which the underlying key molecular events have yet to be addressed.

RESULTS

Here, we identified poly(A) binding protein nuclear 1 (PABPN1), a general factor of alternative polyadenylation (APA), was downregulated in BC. Overexpression and knockdown of PABPN1 significantly decreased and increased BC aggressiveness, respectively. Mechanistically, we provide evidence that the preference of PABPN1-bound polyadenylation signals (PASs) depends on the relative location between canonical and non-canonical PASs. PABPN1 shapes inputs converging on Wnt signaling, cell cycle, and lipid biosynthesis.

CONCLUSIONS

Together, these findings provide insights into how PABPN1-mediated APA regulation contributes to BC progression, and suggest that pharmacological targeting PABPN1 might have therapeutic potential in patients with BC.

Receptor Tyrosine Kinase Pathway and Infiltrating Urothelial Carcinoma

Receptor tyrosine kinase pathway is frequently searched for cancer causing mutations in tumors. Emerging targeted therapies are gleam of hope for them. Infiltrating urothelial carcinoma can have many morphological aspects according to their differentiation/variants. To evaluate KRAS, BRAF, and PIK3CA mutations and HER2, EGFR, and p16 expression, we divided urothelial carcinomas into two groups: differentiated/variants (n = 12) and conventional (n = 12). We compared results with clinical, demographic, histopathologic features and survival rates. No statistically significant results could be obtained in the comparison of histopathologic properties/survival rates with mutation analysis and EGFR, HER2, and p16 status. Differentiated/variants urothelial carcinoma showed higher EGFR expression (P < 0.001). Glandular differentiation was the most frequent type, followed by squamous and sarcomatoid differentiation. We observed the most common mutation at KRAS with a propensity for urothelial carcinoma with glandular differentiation. More than one mutation/high protein expression was seen in some tumors. Targeted therapies for KRAS mutation can be effective at urothelial carcinoma with glandular differentiation. Heterologous expression of relevant proteins and genes can be a cause for targeted treatment obstacle. The determination of the molecular characters of tumors is a guide in creating targeted treatment algorithms and in choosing the patient.

N-(3,4-dimethoxyphenethyl)-6-methyl-2,3,4,9-tetrahydro-1H-carbazol-1-amine inhibits bladder cancer progression by suppressing YAP1/TAZ

Bladder cancer (BlC) is the fourth most common cancer in males worldwide, but few systemic chemotherapy options for its effective treatment exist. The development of new molecularly-targeted agents against BlC is therefore an urgent issue. The Hippo signaling pathway, with its upstream LATS kinases and downstream transcriptional co-activators YAP1 and TAZ, plays a pivotal role in diverse cell functions, including cell proliferation. Recent studies have shown that overexpression of YAP1 occurs in advanced BlCs and is associated with poor patient prognosis. Accessing data from our previous screening of a chemical library of compounds targeting the Hippo pathway, we identified DMPCA (N-(3,4-dimethoxyphenethyl)-6-methyl-2,3,4,9-tetrahydro-1H-carbazol-1-amine) as an agent able to induce the phosphorylation of LATS1 and YAP1/TAZ in BlC cells, thereby suppressing their viability both in vitro and in mouse xenografts. Our data indicate that DMPCA has a potent anti-tumor effect, and raise the possibility that this agent may represent a new and effective therapeutic option for BlC.

Sp1 is overexpressed and associated with progression and poor prognosis in bladder urothelial carcinoma patients

BACKGROUND

Specificity protein 1 (Sp1) is a transcription factor that exerts key functions in the carcinogenesis and progression of various types of cancer. However, its expression and prognostic value in bladder urothelial carcinoma (BUC) have yet to be completely elucidated.

METHODS

The present study performed reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to examine Sp1 mRNA expression in 12 pairs of urothelial carcinoma and adjacent normal bladder tissues. Immunohistochemistry (IHC) was performed in 113 paraffin-embedded urothelial carcinoma tissues to detect the expression of Sp1. Kaplan-Meier plots and Cox proportional hazards regression model were used to analyze the correlation between Sp1 expression and patient prognosis.

RESULTS

The mRNA expression of Sp1 was elevated in the urothelial carcinoma by RT-qPCR compared with their paired normal bladder tissues. Among 113 cases of patients with urothelial carcinoma, there were 39 low histological grade and 74 high histological grade, 61 unifocal tumor and 52 multifocal tumor, 78 cases in Ta, T1, and T2 stages, and 35 cases in T3 and T4 stages. The enhanced expression of Sp1 mRNA was observed in tumors with a high histological grade, and invasive and metastatic samples. Immunohistochemistry revealed that Sp1 high expression was significantly correlated with the histological grade, tumor stage, vascular invasion, lymph node metastasis and distant metastasis (P < 0.05). Kaplan-Meier analysis demonstrated that elevated Sp1 expression in cancer tissue was correlated with a significantly poor overall survival (OS) and disease-free survival (DFS) compared with samples with low Sp1 expression (P < 0.05). Multivariate analyses by Cox's proportional hazard model also revealed that the expression of Sp1 was an independent prognostic factor in urothelial carcinoma.

CONCLUSION

Sp1 expression is significantly elevated in urothelial carcinoma and may be used to identify a subset of patients with aggressive behaviors and poor clinical outcomes. Sp1 is a potential novel independent prognostic biomarker for patients with urothelial carcinoma following surgery.

Rapamycin-induced M2 macrophage autophagy promotes the migration and invasion of bladder cancer cells via increased IL-10 secretion

Intrduction:

Rapamycin is an mTOR inhibitor and a prominent inducer of autophagy in cancer cells and tumor interstitial cells. Macrophages are the primary type of immune cells observed in the tumor microenvironment and serve varying roles in the progression of cancer by polarizing into distinct phenotypes. However, whether rapamycin-induced macrophage autophagy influences bladder cancer remains unclear.

Methods:

THP-1 cells were successfully polarized into M1 or M2 macrophages, which were identified by detecting CD86 (M1) or CD206 (M2) expressions using flow cytometry and measuring M1/M2-related mRNA expressions using reverse transcription-quantitative PCR. Rapamycin was employed for inducing autophagy, and then the influences of enhanced autophagic M1 and M2 macrophages on migration and invasion of bladder cancer cells were confirmed by wound healing and Transwell assay in the co-culture model. Furthermore, the gene and protein expressions of IL-10 and the underlying role are still unclear.

Results:

Rapamycin significantly increased autophagy levels in M1 and M2 macrophages, while only autophagy-enhanced M2 macrophages facilitated the migration and invasion of bladder cancer cells. Furthermore, rapamycin increased IL-10 secretion from M2 macrophages, which mediated the effects of M2 macrophages on migration and invasion of bladder cancer.

Conclusion:

Rapamycin induces M2 macrophage autophagy and promotes the migration and invasion of bladder cancer by increasing IL-10 secretion, suggesting that M2 macrophage autophagy is an underlying target of rapamycin in treating bladder cancer.

MINDY1 promotes bladder cancer progression by stabilizing YAP

Background

Bladder cancer is one of the most commonly diagnosed urological malignant tumor. The Hippo tumor suppressor pathway is highly conserved in mammals and plays an important role in carcinogenesis. YAP is one of major key effectors of the Hippo pathway. However, the mechanism supporting abnormal YAP expression in bladder cancer remains to be characterized.

Methods

Western blot was used to measure the expression of MINDY1 and YAP, while the YAP target genes were measured by real-time PCR. CCK8 assay was used to detect the cell viability. The xeno-graft tumor model was used for in vivo study. Protein stability assay was used to detect YAP protein degradation. Immuno-precipitation assay was used to detect the interaction domain between MINDY1 and YAP. The ubiquitin-based Immuno-precipitation assays were used to detect the specific ubiquitination manner happened on YAP.

Results

In the present study, we identified MINDY1, a DUB enzyme in the motif interacting with ubiquitin-containing novel DUB family, as a bona fide deubiquitylase of YAP in bladder cancer. MINDY1 was shown to interact with, deubiquitylate, and stabilize YAP in a deubiquitylation activity-dependent manner. MINDY1 depletion significantly decreased bladder cancer cell proliferation. The effects induced by MINDY1 depletion could be rescued by further YAP overexpression. Depletion of MINDY1 decreased the YAP protein level and the expression of YAP/TEAD target genes in bladder cancer, including CTGF, ANKRD1 and CYR61.

Conclusion

In general, our findings establish a previously undocumented catalytic role for MINDY1 as a deubiquitinating enzyme of YAP and provides a possible target for the therapy of bladder cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02095-4.

KIF4A promotes the development of bladder cancer by transcriptionally activating the expression of CDCA3

Bladder cancer (BC) is among the most common urinary system tumors with a high morbidity and mortality worldwide. Despite advancements being made in the diagnosis and treatment of bladder cancer, targeted therapy remains the most promising treatment, and novel therapeutic targets are urgently required in to improve the outcomes of patients with BC. Kinesin family member 4A (KIF4A) is a plus-end directed motor protein involved in the regulation of multiple cellular processes, such as mitosis and axon growth. Notably, KIF4A plays important roles in tumor growth and progression, and its expression is associated with the prognosis of several types of cancer. However, the potential role and molecular mechanisms of KIF4A in bladder cancer development remain unclear. The present study demonstrated that KIF4A was highly expressed in human BC tissues, and its expression was associated with patient clinicopathological characteristics, such as tumor stage (P=0.012) and with the prognosis of patients with BC. It was further found that KIF4A promoted the cell proliferation of bladder cancer both in vitro and in vivo. On the whole, the data presented herein provide evidence that KIF4A promotes the development of BC through the transcriptional activation of the expression of CDCA3. The present study indicates the involvement of KIF4A in the progression of BC and suggests that KIF4A may be a promising therapeutic target for the treatment of BC.

Silencing of lncRNA MIR497HG via CRISPR/Cas13d Induces Bladder Cancer Progression Through Promoting the Crosstalk Between Hippo/Yap and TGF-β/Smad Signaling

A subset of long non-coding RNAs (lncRNAs), categorized as miRNA-host gene lncRNAs (lnc-miRHGs), is processed to produce miRNAs and involved in cancer progression. This work aimed to investigate the influences and the molecular mechanisms of lnc-miRHGs MIR497HG in bladder cancer (BCa). The miR-497 and miR-195 were derived from MIR497HG. We identified that lnc-miRHG MIR497HG and two harbored miRNAs, miR-497 and miR-195, were downregulated in BCa by analyzing The Cancer Genome Atlas and our dataset. Silencing of MIR497HG by CRISPR/Cas13d in BCa cell line 5637 promoted cell growth, migration, and invasion in vitro. Conversely, overexpression of MIR497HG suppressed cell progression in BCa cell line T24. MiR-497/miR-195 mimics rescued significantly the oncogenic roles of knockdown of MIR497HG by CRISPR/Cas13d in BCa. Mechanistically, miR-497 and miR-195 co-ordinately suppressed multiple key components in Hippo/Yap and transforming growth factor β signaling and particularly attenuated the interaction between Yap and Smad3. In addition, E2F4 was proven to be critical for silencing MIR497HG transcription in BCa cells. In short, we propose for the first time to reveal the function and mechanisms of MIR497HG in BCa. Blocking the pathological process may be a potential strategy for the treatment of BCa.

Noninvasive Detection of Urothelial Carcinoma by Cost-effective Low-coverage Whole-genome Sequencing from Urine-Exfoliated Cell DNA

PURPOSE

Urothelial carcinoma is a malignant cancer with frequent chromosomal aberrations. Here, we investigated the application of a cost-effective, low-coverage whole-genome sequencing technology in detecting all chromosomal aberrations.

EXPERIMENTAL DESIGN

Patients with urothelial carcinomas and nontumor controls were prospectively recruited in clinical trial NCT03998371. Urine-exfoliated cell DNA was analyzed by Illumina HiSeq XTen, followed by genotyping with a customized bioinformatics workflow named Urine Exfoliated Cells Copy Number Aberration Detector (UroCAD).

RESULTS

In the discovery phase, urine samples from 126 patients with urothelial carcinomas and 64 nontumor disease samples were analyzed. Frequent chromosome copy-number changes were found in patients with tumor as compared with nontumor controls. A novel diagnosis model, UroCAD, was built by incorporating all the autosomal chromosomal changes. The model reached performance of AUC = 0.92 (95% confidence interval, 89.4%-97.3%). At the optimal cutoff, |Z| ≥ 3.21, the sensitivity, specificity, and accuracy were 82.5%, 96.9%, and 89.0%, respectively. The prediction positivity was found correlated with tumor grade (P = 0.01). In the external validation cohort of 95 participants, the UroCAD assay identified urothelial carcinomas with an overall sensitivity of 80.4%, specificity of 94.9%, and AUC of 0.91. Meanwhile, UroCAD assay outperformed cytology tests with significantly improved sensitivity (80.4% vs. 33.9%; P < 0.001) and comparable specificity (94.9% vs. 100%; P = 0.49).

CONCLUSIONS

UroCAD could be a robust urothelial carcinoma diagnostic method with improved sensitivity and similar specificity as compared with cytology tests. It may be used as a noninvasive approach for diagnosis and recurrence surveillance in urothelial carcinoma prior to the use of cystoscopy, which would largely reduce the burden on patients.

Whole Genome Messenger RNA Profiling Identifies a Novel Signature to Predict Gastric Cancer Survival

Molecular prognostic biomarkers for gastric cancer (GC) are still limited. We aimed to identify potential messenger RNAs (mRNAs) associated with GC prognosis and further establish an mRNA signature to predict the survival of GC based on the publicly accessible databases.

Behavioral analysis in mice deficient for GAREM2 (Grb2-associated regulator of Erk/MAPK subtype2) that is a subtype of highly expressing in the brain

Grb2-associated regulator of Erk/MAPK (GAREM), is an adaptor protein related to the several cell growth factor receptor-signaling. The GAREM family has two subtypes, GAREM1 and GAREM2, both encoded in the human and mouse genome. Recent genome-wide research identified GAREM2 as a candidate of neurodegenerative diseases. Here, we use knockout (KO) mice to show the role of GAREM2, that is highly expressed in the brain. According to the comprehensive behavioral battery, they exhibited less anxiety both in elevated plus maze and open field tests, mildly increased social approaching behavior in the reciprocal social interaction test, and longer latency to immobility in the tail suspension test as compared to wild-type (WT). Additionally, the extension of neurites in the primary cultured neurons was suppressed in ones derived from GAREM2 KO mice. Furthermore, we also identified Intersectin, as a binding partner of GAREM2 in this study. Intersectin is also a multi-domain adaptor protein that regulates endocytosis and cell signaling, which can potentially alter the subcellular localization of GAREM2. The important molecules, such as the neurotrophin receptor and Erk family, that are involved in the signaling pathway of the neural cell growth in the mouse brain, have been reported to participate in emotional behavior. As GAREM plays a role in the cellular growth factor receptor signaling pathway, GAREM2 may have a common role related to the transduction of Erk signaling in the higher brain functions.

Extracellular matrix protein 1 (ECM1) is associated with carcinogenesis potential of human bladder cancer

Background

Bladder cancer (BCa) is a common urological malignant tumor worldwide, and recurrence and death still remain high. New therapeutic targets are needed to treat patients who are not sensitive to current therapy. Extracellular matrix protein 1 (ECM1) is a key player in multiple epithelial malignancies. However, the knowledge regarding the expression of ECM1 in BCa and the mechanisms by which ECM1 affects BCa tumor progression is unclear.

Materials and methods

ECM1 expression levels in BCa tissues and cells were detected by quantitative real-time PCR (qRT-PCR), immunohistochemistry and Western blot. ECM1 expression was suppressed by shRNAs. Cell Counting Kit-8 (CCK-8), luminescent cell viability assay and 5-ethynyl-2′-deoxyuridine (EdU) assay were used to detect cell proliferation. Flow cytometry and transwell assay were used to evaluate cell apoptosis and invasion, respectively. All statistical analyses were performed by using the GraphPad Prism 7 software package.

Results

In this study, the expression of ECM1 in BCa specimens and cell lines was examined and displayed a significant increase compared with noncancerous counterparts, while ECM1-knockdown affected not only cell proliferation and migration, but also cell invasion ability and apoptosis potential, corresponding to the finding that ECM1 overexpression in BCa patients was associated with a poor prognosis. Additionally, after suppression of ECM1, the expression of glucose transporter 1 (GLUT1), lactate dehydrogenase (LDHA) and hypoxia-inducible factor 1α (HIF-1α), genes involved in Warburg effect regulation, were significantly decreased, and the lactate production was also obviously reduced in ECM1-silenced cells.

Conclusion

Our investigations revealed that the expression of ECM1 was closely associated with tumor cell growth, migration and apoptosis at least in part through regulation of Warburg effect, defining ECM1 as an effective predictor in the carcinogenesis and postoperative recurrence of human BCa.

TYRO3 as a molecular target for growth inhibition and apoptosis induction in bladder cancer

Background

Muscle-invasive bladder cancer (MIBC) is an aggressive neoplasm with poor prognosis, lacking effective therapeutic targets. Oncogenic dependency on members of the TAM tyrosine kinase receptor family (TYRO3, AXL, MERTK) has been reported in several cancer types, but their role in bladder cancer has never been explored.

Methods

TAM receptor expression was evaluated in two series of human bladder tumours by gene expression (TCGA and CIT series), immunohistochemistry and western blotting analyses (CIT series). The role of the different TAM receptors was assessed by loss-of-function experiments and pharmaceutical inhibition in vitro and in vivo.

Results

We reported a significantly higher expression of TYRO3, but not AXL or MERTK, in both non-MIBCs and MIBCs, compared to normal urothelium. Loss-of-function experiments identified a TYRO3-dependency of bladder carcinoma-derived cells both in vitro and in a mouse xenograft model, whereas AXL and MERTK depletion had only a minor impact on cell viability. Accordingly, TYRO3-dependent bladder tumour cells were sensitive to pharmacological treatment with two pan-TAM inhibitors. Finally, growth inhibition upon TYRO3 depletion relies on cell cycle inhibition and apoptosis associated with induction of tumour-suppressive signals.

Conclusions

Our results provide a preclinical proof of concept for TYRO3 as a potential therapeutic target in bladder cancer.

Epidermal growth factor expression as a predictor of chemotherapeutic resistance in muscle-invasive bladder cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) overexpression is believed to be associated with bladder cancer (BC) progression and poor clinical outcomes. In vivo studies have linked EGFR subcellular trafficking and chemo-resistance to cisplatin-based chemotherapies. This has not been studied in the clinical adjuvant setting. We aimed to investigate the prognostic significance of EGFR expression in patients receiving cisplatin-based adjuvant chemotherapy following radical cystectomy for advanced BC.

METHODS

The database from the Urology and Nephrology Center at Mansoura University was reviewed. BC patients who were treated with radical cystectomy and adjuvant chemotherapy for adverse pathological features or node positive disease were identified. Patients who underwent palliative cystectomy, had histological diagnoses other than pure urothelial carcinoma, or received adjuvant radiotherapy were excluded from the study. Immunohistochemical staining for EGFR expression was performed on archived bladder specimens. The following in vitro functional analyses were performed to study the relationship of EGFR expression and chemoresponse.

RESULTS

The study included 58 patients, among which the mean age was 57 years old. Majority of patients had node positive disease (n = 53, 91%). Mean follow up was 26.61 months. EGFR was overexpressed in 25 cystectomy specimens (43%). Kaplan-Meier analysis revealed that EGFR over-expression significantly correlated with disease recurrence (p = 0.021). Cox proportional hazard modeling identified EGFR overexpression as an independent predictor for disease recurrence (p = 0.04). Furthermore, in vitro experiments demonstrated that inhibition of EGFR may sensitize cellular responses to cisplatin.

CONCLUSIONS

Our findings suggest that EGFR overexpression is associated with disease recurrence following adjuvant chemotherapy for advanced BC. This may aid in patient prognostication and selection prior to chemotherapeutic treatment for BC.

Structural Alterations in Human Fibroblast Growth Factor Receptors in Carcinogenesis

Fibroblast growth factor (FGF) plays an important role in human embryogenesis, angiogenesis, cell proliferation, and differentiation. Carcinogenesis is accompanied by aberrant constitutive activation of FGF receptors (FGFRs) resulting from missense mutation in the FGFR1-4 genes, generation of chimeric oncogenes, FGFR1-4 gene amplification, alternative splicing shift toward formation of mesenchymal FGFR isoforms, and FGFR overexpression. Altogether, these alterations contribute to auto- and paracrine stimulation of cancer cells and neoangiogenesis. Certain missense mutations are found at a high rate in urinary bladder cancer and can be used for non-invasive cancer recurrence diagnostics by analyzing urine cell pellet DNA. Chimeric FGFR1/3 and amplified FGFR1/2 genes can predict cell response to the targeted therapy in various oncological diseases. In recent years, high-throughput sequencing has been used to analyze exomes of virtually all human tumors, which allowed to construct phylogenetic trees of clonal cancer evolution with special emphasis on driver mutations in FGFR1-4 genes. At present, FGFR blockers, such as multi-kinase inhibitors, specific FGFR inhibitors, and FGF ligand traps are being tested in clinical trials. In this review, we discuss current data on the functioning of the FGFR family proteins in both normal and cancer cells, mutations in the FGFR1-4 genes, and mechanisms underlying their oncogenic potential, which might be interesting to a broad range of scientists searching for specific tumor markers and targeted anti-cancer drugs.

Effects of Two-by-Two Combination Therapy with Valproic Acid, Lithium Chloride, and Celecoxib on the Angiogenesis of the Chicken Chorioallantoic Membrane

BACKGROUND

The synergistic effects of valproic acid (VPA), lithium (Li), and celecoxib (CX) have been shown in combination therapy against the proliferation and metastasis of numerous cancers. Angiogenesis plays a critical role in the pathogenesis of tumor growth and metastasis. The aim of the present study was to evaluate the antiangiogenic effects of VPA, lithium chloride (LiCl), and CX, alone or in 2-by-2 combinations, using the chicken chorioallantoic membrane (CAM) assay.

METHODS

Fertilized chicken eggs were randomly divided into 10 groups: control, VPA (1.8 and 3.6 µmol/CAM), Li (0.15 and 0.60 µmol/CAM), CX (0.02 and 0.08 µmol/CAM), VPA+Li, VPA+CX, and CX+Li (n=10 per group). A window was made on the eggshells and the CAMs were exposed to a filter disk containing VPA, LiCl, and CX, alone or in 2-by-2 combinations. The control CAMs were treated with distilled water (vehicle). Three days after the treatment, the number of vessel branch points was counted in each CAM. The data were analyzed using SPSS, version 15.One-way ANOVA, followed by the Tukey tests, was used to compare the groups. A P<0.05 was considered a statistically significant difference between the groups.

RESULTS

According to the results, all the tested drugs decreased the number of the vessel branch points in a dose-dependent manner compared to the control group (P<0.001). In addition, combinations of the drugs were more effective in decreasing angiogenesis than the use of each drug alone.

CONCLUSION

These findings suggest that 2-by-2 combinations of VPA, CX, and LiCl can be considered an effective antiangiogenesis therapeutic modality.

Verteporfin inhibits YAP-induced bladder cancer cell growth and invasion via Hippo signaling pathway

The highly conserved Hippo signaling pathway is one of the most important pathways involved in tumorigenesis and progress. Previous studies show that YAP, the transcriptional coactivator of Hippo pathway, is expressed highly in many clinical bladder cancer tissues and plays crucial role on bladder cancer progress. To find the YAP-specific target drug and its molecular mechanism in bladder cancer, we apply Verteporfin (VP), a YAP specific inhibitor to function as anti-bladder cancer drug and discover that VP is able to inhibit bladder cancer cell growth and invasion in a dosage dependent manner. Moreover, we demonstrate that VP may inhibit bladder cancer cell growth and invasion via repressing target genes' expression of the Hippo signaling pathway. In further study, we provide evidence that VP is able to inhibit excessive YAP induced bladder cancer cell growth and invasion. To address the repressive function of VP against YAP in bladder cancer, we check the target genes' expression and find VP can dramatically repress YAP overexpression induced Hippo pathway target genes' expression. Taken together, we discover that VP inhibits YAP-induced bladder cancer cell growth and invasion via repressing the target genes' expression of Hippo signaling pathway.

An FGFR3/MYC positive feedback loop provides new opportunities for targeted therapies in bladder cancers

FGFR3 alterations (mutations or translocation) are among the most frequent genetic events in bladder carcinoma. They lead to an aberrant activation of FGFR3 signaling, conferring an oncogenic dependence, which we studied here. We discovered a positive feedback loop, in which the activation of p38 and AKT downstream from the altered FGFR3 upregulates MYC mRNA levels and stabilizes MYC protein, respectively, leading to the accumulation of MYC, which directly upregulates FGFR3 expression by binding to active enhancers upstream from FGFR3 Disruption of this FGFR3/MYC loop in bladder cancer cell lines by treatment with FGFR3, p38, AKT, or BET bromodomain inhibitors (JQ1) preventing MYC transcription decreased cell viability in vitro and tumor growth in vivo A relevance of this loop to human bladder tumors was supported by the positive correlation between FGFR3 and MYC levels in tumors bearing FGFR3 mutations, and the decrease in FGFR3 and MYC levels following anti-FGFR treatment in a PDX model bearing an FGFR3 mutation. These findings open up new possibilities for the treatment of bladder tumors displaying aberrant FGFR3 activation.

Unmasking molecular profiles of bladder cancer

Precision medicine is designed to tailor treatments for individual patients by factoring in each person's specific biology and mechanism of disease. This paradigm shifted from a "one size fits all" approach to "personalized and precision care" requires multiple layers of molecular profiling of biomarkers for accurate diagnosis and prediction of treatment responses. Intensive studies are also being performed to understand the complex and dynamic molecular profiles of bladder cancer. These efforts involve looking bladder cancer mechanism at the multiple levels of the genome, epigenome, transcriptome, proteome, lipidome, metabolome etc. The aim of this short review is to outline the current technologies being used to investigate molecular profiles and discuss biomarker candidates that have been investigated as possible diagnostic and prognostic indicators of bladder cancer.

Prostaglandin receptors induce urothelial tumourigenesis as well as bladder cancer progression and cisplatin resistance presumably via modulating PTEN expression

BACKGROUND

We investigated the role of prostaglandin receptors (e.g. prostaglandin E2 receptor 2 (EP2), EP4) and the efficacy of celecoxib in urothelial tumourigenesis and cancer progression.

METHODS

We performed immunohistochemistry in bladder cancer (BC) tissue microarrays, in vitro transformation assay in a normal urothelial SVHUC line, and western blot/reverse transcription-polymerase chain reaction/cell growth assays in BC lines.

RESULTS

EP2/EP4 expression was elevated in BCs compared with non-neoplastic urothelial tissues and in BCs from those who were resistant to cisplatin-based neoadjuvant chemotherapy. Strong positivity of EP2/EP4 in non-muscle-invasive tumours or positivity of EP2/EP4 in muscle-invasive tumours strongly correlated with disease progression or disease-specific mortality, respectively. In SVHUC cells, exposure to a chemical carcinogen 3-methylcholanthrene considerably increased and decreased the expression of EP2/EP4 and phosphatase and tensin homologue (PTEN), respectively. Treatment with selective EP2/EP4 antagonist or celecoxib also resulted in prevention in 3-methylcholanthrene-induced neoplastic transformation of SVHUC cells. In BC lines, EP2/EP4 antagonists and celecoxib effectively inhibited cell viability and migration, as well as augmented PTEN expression. Furthermore, these drugs enhanced the cytotoxic activity of cisplatin in BC cells. EP2/EP4 and PTEN were also elevated and reduced, respectively, in cisplatin-resistant BC sublines.

CONCLUSIONS

EP2/EP4 activation correlates with induction of urothelial cancer initiation and outgrowth, as well as chemoresistance, presumably via downregulating PTEN expression.

Discovery of Bladder Cancer-related Genes Using Integrative Heterogeneous Network Modeling of Multi-omics Data

In human health, a fundamental challenge is the identification of disease-related genes. Bladder cancer (BC) is a worldwide malignant tumor, which has resulted in 170,000 deaths in 2010 up from 114,000 in 1990. Moreover, with the emergence of multi-omics data, more comprehensive analysis of human diseases become possible. In this study, we propose a multi-step approach for the identification of BC-related genes by using integrative Heterogeneous Network Modeling of Multi-Omics data (iHNMMO). The heterogeneous network model properly and comprehensively reflects the multiple kinds of relationships between genes in the multi-omics data of BC, including general relationships, unique relationships under BC condition, correlational relationships within each omics and regulatory relationships between different omics. Besides, a network-based propagation algorithm with resistance is utilized to quantize the relationships between genes and BC precisely. The results of comprehensive performance evaluation suggest that iHNMMO significantly outperforms other approaches. Moreover, further analysis suggests that the top ranked genes may be functionally implicated in BC, which also confirms the superiority of iHNMMO. In summary, this study shows that disease-related genes can be better identified through reasonable integration of multi-omics data.

Next-generation sequencing of urine specimens: A novel platform for genomic analysis in patients with non-muscle-invasive urothelial carcinoma treated with bacille Calmette-Guérin

BACKGROUND

Biopsies from patients with high-risk (HR) non-muscle-invasive urothelial carcinoma (NMIUC), especially flat urothelial carcinoma in situ, frequently contain scant diagnostic material or denuded mucosa only, and this precludes further extensive genomic analysis. This study evaluated the use of next-generation sequencing (NGS) analysis of urine cytology material from patients with HR NMIUC in an attempt to identify genetic alterations that might correlate with clinical features and responses to bacille Calmette-Guérin (BCG) treatment.

METHODS

Forty-one cytology slides from patients with HR NMIUC treated with intravesical BCG were selected for this study. Histological confirmation was available for all cases. The specimens were subjected to NGS analysis with a customized targeted exome capture assay composed of 341 genes.

RESULTS

In this cohort, genomic alterations were successfully identified in all cytology samples. Mutations were detected down to a 2% allele frequency and chromosomal rearrangements including copy number alterations and gene fusions were identified. The most frequently altered genes included telomerase reverse transcriptase (TERT), tumor protein 53 (TP53), Erb-B2 receptor tyrosine kinase 2 (ERBB2), and chromatin remodeling genes such as lysine demethylase 6A (KDM6A) and AT-rich interaction domain 1A (ARID1A). For patients with matched tumor tissue, cytology specimens revealed all mutations detected in tissue as well as additional mutations, and this suggested that urine might more effectively capture the full genetic heterogeneity of disease than an individual cystectomy. Alterations in multiple genes correlated with clinical and histopathological features, including responses to BCG treatment, flat architecture versus papillary architecture, and smoking history.

CONCLUSIONS

Urine specimens can replace tissue as a substrate for NGS analysis of HR NMIUC. Several genomic alterations identified in urine specimens might be associated with histological features and clinical characteristics. Cancer Cytopathol 2017;125:416-26. © 2017 American Cancer Society.

Proteomic analysis of proteome and histone post-translational modifications in heat shock protein 90 inhibition-mediated bladder cancer therapeutics

Heat shock protein 90 (HSP90) inhibition is an attractive strategy for cancer treatment. Several HSP90 inhibitors have shown promising effects in clinical oncology trials. However, little is known about HSP90 inhibition-mediated bladder cancer therapy. Here, we report a quantitative proteomic study that evaluates alterations in protein expression and histone post-translational modifications (PTMs) in bladder carcinoma in response to HSP90 inhibition. We show that 5 HSP90 inhibitors (AUY922, ganetespib, SNX2112, AT13387, and CUDC305) potently inhibited the proliferation of bladder cancer 5637 cells in a dose- and time-dependent manner. Our proteomic study quantified 518 twofold up-regulated and 811 twofold down-regulated proteins common to both AUY922 and ganetespib treatment. Bioinformatic analyses revealed that those differentially expressed proteins were involved in multiple cellular processes and enzyme-regulated signaling pathways, including chromatin modifications and cell death-associated pathways. Furthermore, quantitative proteome studies identified 14 types of PTMs with 93 marks on the core histones, including 34 novel histone marks of butyrylation, citrullination, 2-hydroxyisobutyrylation, methylation, O-GlcNAcylation, propionylation, and succinylation in AUY922- and ganetespib-treated 5637 cells. Together, this study outlines the association between proteomic changes and histone PTMs in response to HSP90 inhibitor treatment in bladder carcinoma cells, and thus intensifies the understanding of HSP90 inhibition-mediated bladder cancer therapeutics.

Immunohistochemical Investigation of HER/AKT/mTOR Pathway and Cellular Adhesion Molecules in Urothelial Carcinomas

Background. Several investigators have suggested the possibility that the expression of both EGFR and HER2 could be utilized for molecularly targeted therapy in urinary bladder cancer. We tried to evaluate the expression of HER2 and EGFR and activation of the AKT/PTEN/mTOR pathway in urothelial carcinomas and if there is any association between them and cellular adhesion molecules (CAMs). Materials and Methods. Forty-one paraffin-embedded urothelial cancer tissue blocks were collected. Immunostains for HER2, EGFR, MIB1, phospho-AKT, PTEN, phospho-mTOR, e-cadherin, p-cadherin, and b-catenin were performed on tissue microarrays sections. The immunohistochemical results were correlated with clinicopathological parameters. Results. The overexpression of HER2 was found in 19.6% of the cases and it was associated with high grade tumors with a high mitotic index and phosphorylation of AKT and mTOR. Muscle-invasive tumors presented both cytoplasmic and nuclear losses of PTEN expression. There was no association between HER/AKT/mTOR pathway activation and CAM expression. Although cadherins were often coexpressed, only p-cadherin immunoreactivity was associated with tumor grade and high proliferative index. Conclusions. HER2 overexpression is found in a respective proportion of urothelial carcinomas. P-cadherin expression is associated with high grade UCs but it is not affected by HER2 overexpression or by activation of HER/AKT/mTOR pathway.

Transcriptional cofactor Mask2 is required for YAP-induced cell growth and migration in bladder cancer cell

The highly conserved Hippo signaling pathway is an important pathway involved in tumorigenesis and development. In previous studies, YAP, the transcription coactivator of Hippo pathway, is found to be highly expressed in many clinical bladder cancer samples. To investigate the function of YAP and its cofactor Mask2 in bladder cancer, we overexpress YAP in bladder cancer cells and discover that YAP is able to promote bladder cancer cell growth and migration. In addition, we provide evidence that knockdown of Mask2 is able to repress bladder cancer cell growth and migration. Furthermore, we demonstrate knockdown of Mask2 is able to inhibit bladder cancer cell growth and migration induced by the excessive YAP. To explain the function of YAP/Mask2 complex in bladder cancer, we check the target genes' expression of Hippo signaling pathway involved in cell growth and migration and find overexpressed YAP is able to upregulate the target genes' expression while depletion of Mask2 downregulates them. Taken together, we demonstrate that Mask2 is required for the function of bladder cancer cell growth and migration induced by YAP via the target genes of Hippo pathway.

Systemic therapy for bladder cancer finally comes into a new age

Systemic therapy for bladder cancer, both localized muscle-invasive disease and metastatic disease, has seen minimal progress over the past two decades. Current approaches rely upon cytotoxic chemotherapy combinations aimed at increasing cure rates or achieving palliation and disease control, but these regimens are fraught with short- and long-term toxicities and outcomes remain suboptimal. The emergence of systemic immunotherapies that can provide durable remissions in subsets of patients with other malignancies has the potential to transform the field, and early phase trials have begun to demonstrate activity in some patients with metastatic bladder cancer. In this article, we review the current state of systemic therapy for bladder cancer and discuss the current literature and ongoing trials utilizing various immunotherapies.

Using the neoadjuvant chemotherapy paradigm to develop precision therapy for muscle-invasive bladder cancer

BACKGROUND

Bladder cancer is a leading cause of morbidity and mortality. Despite recent advances in understanding its molecular biology, the 5-year survival for muscle-invasive disease (muscle-invasive bladder cancer [MIBC]) remains approximately 50%. Although neoadjuvant chemotherapy (NAC) offers an established 5% absolute survival benefit at 5 years, only the 40% of patients with a major tumor response appear to benefit. There remains, therefore, a critical unmet need for predictive markers to determine which patients are best managed with NAC, as well as for novel targeted therapies to overcome resistance to NAC.

METHODS

The NAC paradigm offers the optimal clinical context for developing precision therapy for MIBC. Abundant tissue is available for analysis before NAC in all patients and after NAC in patients with residual MIBC. Technologic advances have enabled next-generation sequencing and gene expression microarray analysis of routinely collected and even archived tissue specimens. These technologies provide a foundation for the identification of markers of chemoresistance and for the development of rational cotargeting strategies.

RESULTS

Modern computational methods allow for some measure of target validation, which can be enhanced by the use of patient-derived primary xenografts (PDX). These PDX can be established at the time of radical cystectomy after NAC if there is residual MIBC. By the time a patient recurs clinically, candidate drugs targeting specific molecular changes in the patient tumor and corresponding PDX would have been tested in the PDX model, and only the most efficacious drug(s) would be administered to the patient. Liquid biopsies in the form of circulating tumor DNA and circulating tumor cells allow noninvasive longitudinal monitoring of the molecular landscape of an advanced tumor as it is being treated with successive courses of systemic therapy.

CONCLUSIONS

These tools combined form the foundation of an evidence-based precision oncology strategy for MIBC.

Histone deacetylase inhibitor-induced cell death in bladder cancer is associated with chromatin modification and modifying protein expression: A proteomic approach

The Cancer Genome Atlas (TCGA) project recently identified the importance of mutations in chromatin remodeling genes in human carcinomas. These findings imply that epigenetic modulators might have a therapeutic role in urothelial cancers. To exploit histone deacetylases (HDACs) as targets for cancer therapy, we investigated the HDAC inhibitors (HDACIs) romidepsin, trichostatin A, and vorinostat as potential chemotherapeutic agents for bladder cancer. We demonstrate that the three HDACIs suppressed cell growth and induced cell death in the bladder cancer cell line 5637. To identify potential mechanisms associated with the anti-proliferative and cytotoxic effects of the HDACIs, we used quantitative proteomics to determine the proteins potentially involved in these processes. Our proteome studies identified a total of 6003 unique proteins. Of these, 2472 proteins were upregulated and 2049 proteins were downregulated in response to HDACI exposure compared to the untreated controls (P<0.05). Bioinformatic analysis further revealed that those differentially expressed proteins were involved in multiple biological functions and enzyme-regulated pathways, including cell cycle progression, apoptosis, autophagy, free radical generation and DNA damage repair. HDACIs also altered the acetylation status of histones and non-histone proteins, as well as the levels of chromatin modification proteins, suggesting that HDACIs exert multiple cytotoxic actions in bladder cancer cells by inhibiting HDAC activity or altering the structure of chromatin. We conclude that HDACIs are effective in the inhibition of cell proliferation and the induction of apoptosis in the 5637 bladder cancer cells through multiple cell death-associated pathways. These observations support the notion that HDACIs provide new therapeutic options for bladder cancer treatment and thus warrant further preclinical exploration.